Auxiliary Air Valve Vacuum Line
 

The Auxiliary Air system valve on my 96 328IS appears to be operated by a vacuum line. The rubber vacuum tube runs from the valve to a metal tube that passes around the front of engine (from left to right facing the engine) and then reconnects to a rubber tube that then connects to an in-line check valve. From the check valve (I assume) there is another rubber tube that connects somewhere with the intake manifold. It appears that the vacuum line running from the manifold to the check valve has become disconnected. I have been unable to find this line so that it can be reconnected. Does anyone know how/where this vacuum line is routed? I am trying to avoid any unnecessary disassembly. Thanks